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RE: Antarctica
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New research provides insight into ice sheet behaviour
A new study published this week takes scientists a step further in their quest to understand how Antarctica's vast glaciers will contribute to future sea-level rise.  Reporting in the journal Nature Geoscience,  scientists from British Antarctic Survey (BAS) and University of Durham describe how a new 3-d map created from radar measurements reveals features in the landscape beneath a  vast river of ice, ten times wider than the Rhine, in the West Antarctic Ice Sheet.

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Imagine a lush, green and humid rainforest approximately 1 ½ times the size of the United States, filled with dinosaurs and dense thickets of palm trees and cycads.
Now imagine it at the South Pole, spanning the whole of Antarctica.
It's the new snapshot of what Antarctica looked like millions of years ago, as described by scientists who study the region.

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East Antarctic ice sheet
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Incredible peaks and valleys, buried beneath ice for 14 million years, have revealed evidence of how the East Antarctic ice sheet first formed.
Scientists used radar to map an area of the Gamburtsev mountains - believed to be the point of origin of the ice.
The region would have been cold enough for the first glacier to form.
Writing in the journal Nature, the researchers say their findings provide important clues about how the ice sheet will behave as our climate changes.

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Threat from West Antarctica less than previously believed
The potential contribution to sea level rise from a collapse of the West Antarctic Ice Sheet (WAIS) have been greatly overestimated, according to a new study published in the journal Science.  Scientists estimate global sea level would rise 3.3 metres, not five or six, as previously thought.  The Atlantic and Pacific seaboards of the US, even in the case of a partial collapse, would experience the largest increases, threatening cities such as New York, Washington DC and San Francisco.

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Larsen Ice Shelf
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Title: Coastal-Change and Glaciological Map of the Larsen Ice Shelf Area, Antarctica: 19402005
Authors: Jane G. Ferrigno, Alison J. Cook, Amy M. Mathie, Richard S. Williams, Jr., Charles Swithinbank, Kevin M. Foley, Adrian J. Fox, Janet W. Thomson, and Jörn Sievers

Changes in the area and volume of polar ice sheets are intricately linked to changes in global climate, and the resulting changes in sea level could severely impact the densely populated coastal regions on Earth. Antarctica is Earths largest reservoir of glacial ice. Melting of the West Antarctic part alone of the Antarctic ice sheet would cause a sea-level rise of approximately 6 meters (m), and the potential sea-level rise after melting of the entire Antarctic ice sheet is estimated to be 65 m (Lythe and others, 2001) to 73 m (Williams and Hall, 1993). The mass balance (the net volumetric gain or loss) of the Antarctic ice sheet is highly complex, responding differently to different climatic and other conditions in each region (Vaughan, 2005). In a review paper, Rignot and Thomas (2002) concluded that the West Antarctic ice sheet is probably becoming thinner overall; although it is known to be thickening in the west, it is thinning in the north. The mass balance of the East Antarctic ice sheet is thought by Davis and others (2005) to be positive on the basis of the change in satellite-altimetry measurements made between 1992 and 2003.

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Wilkins Ice Shelf
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Satellite images show that icebergs have begun to calve from the northern front of the Wilkins Ice Shelf indicating that the huge shelf has become unstable. This follows the collapse three weeks ago of the ice bridge that had previously linked the Antarctic mainland to Charcot Island.

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RE: Antarctica
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Ice is expanding in much of Antarctica, contrary to the widespread public belief that global warming is melting the continental ice cap.
The results of ice-core drilling and sea ice monitoring indicate there is no large-scale melting of ice over most of Antarctica, although experts are concerned at ice losses on the continent's western coast.

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Scientists have uncovered an ancient ecosystem below an Antarctic glacier that survived millions of years in cold brine without light or oxygen, a study said.
Because the ecosystem was isolated for so long in extreme conditions, it could shed light on possible extraterrestrial life and how systems can survive under ice, said long-time Antarctic researcher and Montana State University professor John Priscu, a co-author of the study.


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Hidden in the bone-chilling dark beneath an Antarctic glacier, a colony of strange bacteria is thriving. Scientists investigating the flow of blood-red water from beneath the glacier discovered the bacteria, which have survived for millions of years, living on sulphur and iron compounds, they report in Friday's edition of the journal Science.

"Among the big questions here are: 'How does an ecosystem function below glaciers?', 'How are they able to persist below hundreds of meters of ice and live in permanently cold and dark conditions for extended periods of time, in the case of Blood Falls, over millions of years?" - lead researcher Jill Mikucki of Harvard University.

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Lake Ellsworth
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A Durham University expert is joining an international team of scientists set to explore one of the planet's last great frontiers - an ancient lake hidden deep beneath Antarctica's ice sheet.
Buried under 3 km of ice, the lake - the size of Lake Windermere (UK) - may have been isolated for hundreds of thousands of years and could contain unique forms of life. The team hopes the exploration will yield vital clues about life on Earth, climate change and future sea-level rise.

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